MPxIkSolver Class Reference

#include <MPxIkSolver.h>

Class Description

OBSOLETE CLASS: Base class for user defined IK solvers.

Deprecated:

This class is obsolete and will be removed in a future version of Maya. It has been replaced with the MPxIkSolverNode class.

This is the obsolete base class for writing user-defined IK solvers. Users must at least override the following methods in order to write a solver:

• doSolve
• solverTypeName
• isSingleChainOnly
• isPositionOnly
• hasJointLimitSupport
• hasUniqueSolution
• groupHandlesByTopology

Users can optionally override the following methods if they want to perform work before or after doSolve is called:

• preSolve
• postSolve

If users override these methods, they are responsible for calling the base class implementation of the overridden method(s). The base class handles a few things such as solver locking/unlocking and FK/IK solution blending. If users fail to call the base class implementation, instabilities can occur leading to wrong evaluation or even crashes.

To register a solver, write a creator method to return an instance of the user solver:

userSolver::creator() {
    return new userSolver;
}

The solver can then be registered using MFnPlugin::registerSolver.

Once the solver is registered it can be assigned to IK handles and its solve methods will be called in the same manner as the solvers within Maya.

Public Member Functions
virtual	~MPxIkSolver ()
	Destructor. More...
virtual MStatus	preSolve ()
	This method is called before doSolve. More...
virtual MStatus	doSolve ()
	This is where the main solving takes place. More...
virtual MStatus	postSolve (MStatus)
	This method is called after doSolve has finished. More...
virtual MString	solverTypeName () const
	This method returns the type name of the solver. More...
virtual bool	isSingleChainOnly () const
	This method indicates whether this solver is a single chain solver. More...
virtual bool	isPositionOnly () const
	Indicates whether the solver supports handle orientation. More...
virtual bool	hasJointLimitSupport () const
	This method indicates whether the solver supports limits on joint angles. More...
virtual bool	hasUniqueSolution () const
	This method indicates whether the solver provides a unique solution. More...
virtual bool	groupHandlesByTopology () const
	Indicates whether the IK system should group handles according to skeletal topology. More...
virtual MStatus	setFuncValueTolerance (double tolerance)
	Set the error value for this solver. More...
virtual MStatus	setMaxIterations (int value)
	Set the maximum iterations for a solution by this solver. More...
MIkHandleGroup *	handleGroup () const
	Returns the handle group for this solver. More...
virtual void	setHandleGroup (MIkHandleGroup *)
	Set the handle group of this solver. More...
const MMatrix *	toWorldSpace () const
	Returns the world space matrix for this solver. More...
const MMatrix *	toSolverSpace () const
	Returns the local space matrix for this solver. More...
double	funcValueTolerance () const
	Return the error value for this solver. More...
int	maxIterations () const
	Return the the maximum nuber of itertations for a solution by this solver. More...
virtual void	snapHandle (MObject &handle)
	This function positions the handle at the end effector position. More...

Static Public Member Functions
static const char *	className ()
	Returns the name of this class. More...

Protected Member Functions
MStatus	getJointAngles (MDoubleArray &) const
	Returns the joint angles. More...
MStatus	setJointAngles (const MDoubleArray &)
	Set joint angles to the given values. More...
void	setToRestAngles ()
	Sets all joints to thier prefered orientations.
	MPxIkSolver ()
	Constructor.

Constructor & Destructor Documentation

~MPxIkSolver ( )

virtual

Destructor.

Local class data should be freed here.

Member Function Documentation

MStatus preSolve ( )

virtual

This method is called before doSolve.

Users should override this method if there is any preprocessing that needs to be done before solving..

If this method is overridden, users are responsible for calling base class version MPxIkSolver::preSolve.

Returns

The status code which indicates if the pre-processing was successful

MStatus doSolve ( )

virtual

This is where the main solving takes place.

The user must override this method.

The purpose of this method is to calculate joint angles in a skeleton based upon the position of the end effector of the handle associated with this solver.

Returns

The status code which indicates if the solver was successful

MStatus postSolve ( MStatus  stat )

virtual

This method is called after doSolve has finished.

The user should override this method if there are any post calculations to be done.

If this method is overridden, users are responsible for calling base class version MPxIkSolver::postSolve.

The status argument indicates whether doSolve was successful.

Parameters

[out]

stat

The status returned from doSolve

Returns

Status code to indicate whether the post calculations were successful

MString solverTypeName ( ) const

virtual

This method returns the type name of the solver.

The user must override this method in order for the solver to be identifiable when it is registered. Once the solver is registered, the type name can be used to assign the solver to an ik handle.

Returns

The type name of this solver

bool isSingleChainOnly ( ) const

virtual

This method indicates whether this solver is a single chain solver.

Single chain solvers are solvers which act on one handle only, i.e. the handle groups have only one handle if they are for single chain solvers.

Returns

• true This is a single chain solver
• false This is not a single chain solver

bool isPositionOnly ( ) const

virtual

Indicates whether the solver supports handle orientation.

This method must be overridden to reflect the users solver.

Returns

• true the solver does not support handle orientation
• false the solver supports handle orientation

bool hasJointLimitSupport ( ) const

virtual

This method indicates whether the solver supports limits on joint angles.

This method must be overridden to reflect the users solver.

Returns

• true solver supports joint limits
• false solver does not support joint limits

bool hasUniqueSolution ( ) const

virtual

This method indicates whether the solver provides a unique solution.

This method must be overridden to reflect the users solver.

Returns

• true solver has a unique solution
• false solver does not have a unique solution

bool groupHandlesByTopology ( ) const

virtual

Indicates whether the IK system should group handles according to skeletal topology.

This method must be overridden to reflect the users solver.

Returns

• true solver groups handles by topology
• false solver does not groups handles by topology

MStatus setFuncValueTolerance ( double  tolerance )

virtual

Set the error value for this solver.

The user can override this if any other calcluations should be done here.

Parameters

[in]

tolerance

Error value

Returns

Status code

MStatus setMaxIterations ( int  value )

virtual

Set the maximum iterations for a solution by this solver.

The user can override this if any other calcluations should be done here.

Parameters

[in]

value

value to set

Returns

Status code

MIkHandleGroup * handleGroup

(

)

const

Returns the handle group for this solver.

The handle group provides access to handles associated with the solver.

Returns

A pointer to the ik handle group for this solver

void setHandleGroup ( MIkHandleGroup *  group )

virtual

Set the handle group of this solver.

Parameters

[in]

group

The handle group to be set

const MMatrix * toWorldSpace

(

)

const

Returns the world space matrix for this solver.

Returns

The world space matrix

const MMatrix * toSolverSpace

(

)

const

Returns the local space matrix for this solver.

Returns

The local space matrix

double funcValueTolerance

(

)

const

Return the error value for this solver.

Returns

The error value

int maxIterations

(

)

const

Return the the maximum nuber of itertations for a solution by this solver.

Returns

The maximum number of iterations

void snapHandle ( MObject &  handle )

virtual

This function positions the handle at the end effector position.

The user can override this method.

Parameters

[in]

handle

handle to be set

const char * className ( )

static

Returns the name of this class.

Returns

Name of this class.

MStatus getJointAngles ( MDoubleArray &  angles ) const

protected

Returns the joint angles.

Parameters

[out]

angles

The array of doubles to hold the angles.

Returns

• MS::kSuccess The operation was successfull.
• MS::kFailure The operation failed.

MStatus setJointAngles ( const MDoubleArray &  angles )

protected

Set joint angles to the given values.

Parameters

[in]

angles

The array of angles to set the joints to.

Returns

• MS::kSucces the joint angles were set
• MS::kFailure the joint angles were not set

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The documentation for this class was generated from the following files:

• MPxIkSolver.h
• MPxIkSolver.cpp